From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41500) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1chGjk-00063h-Ms for qemu-devel@nongnu.org; Fri, 24 Feb 2017 09:20:45 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1chGjh-0001Y8-HU for qemu-devel@nongnu.org; Fri, 24 Feb 2017 09:20:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39394) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1chGjh-0001Xb-BP for qemu-devel@nongnu.org; Fri, 24 Feb 2017 09:20:41 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8A3C54E4C5 for ; Fri, 24 Feb 2017 14:20:41 +0000 (UTC) References: <20170206173306.20603-1-dgilbert@redhat.com> <20170206173306.20603-6-dgilbert@redhat.com> From: Laurent Vivier Message-ID: Date: Fri, 24 Feb 2017 15:20:38 +0100 MIME-Version: 1.0 In-Reply-To: <20170206173306.20603-6-dgilbert@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 05/16] postcopy: enhance ram_block_discard_range for hugepages List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" , qemu-devel@nongnu.org, quintela@redhat.com Cc: aarcange@redhat.com On 06/02/2017 18:32, Dr. David Alan Gilbert (git) wrote: > From: "Dr. David Alan Gilbert" > > Unfortunately madvise DONTNEED doesn't work on hugepagetlb > so use fallocate(FALLOC_FL_PUNCH_HOLE) > qemu_fd_getpagesize only sets the page based off a file > if the file is from hugetlbfs. > > Signed-off-by: Dr. David Alan Gilbert > --- > exec.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/exec.c b/exec.c > index e040cdf..c25f6b3 100644 > --- a/exec.c > +++ b/exec.c You should move here the "#include" from PATCH 04/16 +#ifdef CONFIG_FALLOCATE_PUNCH_HOLE +#include +#include +#endif > @@ -3324,9 +3324,20 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length) > > errno = ENOTSUP; /* If we are missing MADVISE etc */ > > + if (rb->page_size == qemu_host_page_size) { > #if defined(CONFIG_MADVISE) > - ret = qemu_madvise(host_startaddr, length, QEMU_MADV_DONTNEED); > + ret = qemu_madvise(host_startaddr, length, QEMU_MADV_DONTNEED); > #endif > + } else { > + /* Huge page case - unfortunately it can't do DONTNEED, but > + * it can do the equivalent by FALLOC_FL_PUNCH_HOLE in the > + * huge page file. > + */ > +#ifdef CONFIG_FALLOCATE_PUNCH_HOLE > + ret = fallocate(rb->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, > + start, length); > +#endif > + } > if (ret) { > ret = -errno; > error_report("ram_block_discard_range: Failed to discard range " > Reviewed-by: Laurent Vivier